JP6551820B2 - Combustor and gas turbine provided with the same - Google Patents

Description

  The present invention relates to a combustor and a gas turbine including the combustor.

  For example, a combustor disclosed in the following Patent Document 1 includes a plurality of burners and a combustion cylinder that forms a combustion region in which fuel ejected from the plurality of burners burns. Each of the plurality of burners includes a nozzle that has a rod-like portion and injects fuel, and a cylinder that surrounds the outer periphery of the nozzle and injects air and fuel from the nozzle downstream. The combustor further includes a substrate extending in a radial direction with respect to the axis of the burner cylinder.

JP, 2006-078127, A

  In the combustor, fuel burns and combustion gas generated as a result of this combustion flows. For this reason, the combustor has a plurality of parts placed in a high temperature environment. Therefore, there is a demand for prolonging the life of a combustor including such components.

  Then, an object of this invention is to provide the combustor which can aim at lifetime improvement, and a gas turbine provided with the same.

A combustor as one aspect according to the invention for achieving the above object is as follows:
A nozzle having a rod-like portion centered on the burner axis, a nozzle for injecting fuel, and a tubular shape surrounding the outer periphery of the nozzle and extending from the upstream side which is one side in the axial direction from which the burner axis extends The burner cylinder which ejects the air and the fuel from the nozzle, and the downstream end of the burner cylinder in a direction having a radial component based on the burner axis, And a substrate for defining a purge air space into which purge air flows on the upstream side of the substrate, and the purge air in the purge air space is in the burner cylinder or downstream of the substrate A purge air flow path that is ejected to the substrate is formed in at least one of the substrate and the burner cylinder. The ejection opening for ejecting the purge air in the purge air flow path has a plate thickness dimension of a cylinder forming plate that forms the burner cylinder and a plate thickness dimension of the substrate from the downstream end of the burner cylinder toward the upstream side. Among these, from the range up to the first opening formation range dimension, which is the longer plate thickness dimension, and the range from the inner peripheral surface of the burner tube to the first opening formation range dimension in the radial direction It forms in the 1st opening formation range which comprises.

  In the combustor, purge air from the purge air space is ejected from the ejection opening of the purge air flow path formed in the opening formation range to the downstream side of the burner cylinder or the substrate. For this reason, in the combustor, it is difficult to form a swirl of combustible gas containing fuel on the downstream side of the downstream end of the burner cylinder. Even if a part of the combustible gas ejected from the burner cylinder drifts in the vicinity of the downstream end of the burner cylinder, the combustible component in the combustible gas is diluted by the purge air. In other words, the purge air from the purge air flow path floats near the downstream end of the burner cylinder, and the combustible component in the combustible gas floating near the downstream end of the burner cylinder decreases.

  Therefore, in the combustor, combustion of combustible gas in the vicinity of the downstream end of the burner cylinder can be suppressed.

A combustor as another aspect according to the invention for achieving the above object is as follows:
A nozzle having a rod-shaped portion centered on the burner axis, and a nozzle for injecting fuel, and surrounding the outer periphery of the nozzle in a cylindrical shape, from the upstream side, which is one side in the axial direction in which the burner axis extends, to the other The burner cylinder which ejects the air and the fuel from the nozzle, and the downstream end of the burner cylinder in a direction having a radial component based on the burner axis, And a substrate for defining a purge air space into which purge air flows on the upstream side of the substrate, and the purge air in the purge air space is in the burner cylinder or downstream of the substrate A purge air flow path that is ejected to the substrate is formed in at least one of the substrate and the burner cylinder. The thickness of the cylinder forming plate that forms the burner cylinder and the thickness of the substrate are from the downstream end of the burner cylinder to the upstream side of the ejection opening that ejects the purge air in the purge air flow channel. And the range up to the second opening formation range dimension which is the shorter plate thickness dimension, and the range from the inner peripheral surface of the burner tube to the second opening formation range dimension in the radial direction. It may be formed in the 2nd opening formation range which consists of.

  In the combustor, the purge air from the purge air space is jetted from the jet opening of the purge air flow path formed in the second opening formation range to the downstream side of the inside of the burner cylinder or the substrate than the burner opening. This second opening formation range is the dimension from the downstream end of the burner cylinder toward the upstream side to the limit position of the second opening formation range, and the second opening formation range from the inner peripheral surface of the burner cylinder toward the radial direction. The dimension to the limit position is shorter than the corresponding dimension of the first opening formation range. Therefore, in the combustor, the amount of purge air drifting from the purge air flow path increases near the downstream end of the burner cylinder, and the combustible content in the combustible gas drifting near the downstream end of the burner cylinder decreases. .

Here, in the combustor according to any one of the above one aspect and the other aspect, the ejection opening may be annularly formed around the burner axis.

  In the combustor, the amount of combustible gas drifting in the vicinity of the entire circumference of the downstream end of the burner cylinder can be reduced.

Further, in the combustor according to any one of the one aspect and the other aspect, a plurality of the ejection openings may be formed apart from each other in a circumferential direction around the burner axis.

  Further, in any one of the above-described combustors, at least one of the inlet opening through which the purge air flows in the purge air flow passage and the ejection opening is circumferentially centered on the burner axis. A plurality of the openings may be formed apart from each other, and the plurality of the one openings may be formed in an arc shape around the burner axis.

  In the combustor, since a space between the plurality of one openings forms a spacer for securing a space between the inner peripheral edge and the outer peripheral edge of the arc-shaped one opening, the inner peripheral edge and the outer peripheral edge of the one opening Interval can be easily secured.

  Further, in the combustor in which at least one of the inlet opening and the ejection opening is formed apart from each other in the circumferential direction, a gap between the plurality of the one openings in the circumferential direction is an arc shape. A spacer is provided to secure a distance between the inner peripheral edge and the outer peripheral edge of the one opening, and the spacer gradually decreases in width in the circumferential direction as it approaches the ejection opening from the purge air space side. May be

  In the combustor, the vortex formed on the downstream side of the spacer can be reduced. Here, the downstream side means the downstream side of the purge air flow in the purge air flow path.

  In any of the above combustors, the ejection opening may be formed to straddle the substrate and the burner cylinder.

  In the combustor, the amount of purge air drifting from the purge air flow path increases near the downstream end of the burner cylinder, and the combustible content in the combustible gas drifting near the downstream end of the burner cylinder can be reduced. .

  In any of the above combustors, the ejection opening may be formed in the burner cylinder.

  In the combustor, the amount of purge air drifting from the purge air flow path increases near the downstream end of the burner cylinder, and the combustible content in the combustible gas drifting near the downstream end of the burner cylinder can be reduced. .

  In any of the above combustors, the ejection opening may be formed in the substrate.

  Further, in any of the above-described combustors, the purge air flow path may be inclined so as to gradually approach the burner axis as it approaches the ejection opening from the purge air space side.

  In the combustor, purge air is injected gradually in the direction approaching the burner axis as it goes downstream from the ejection opening. For this reason, in the combustor, the spread of the flammable gas ejected from the burner cylinder in the radial direction with respect to the burner axis can be suppressed. Therefore, in the combustor, the combustible content in the combustible gas drifting in the vicinity of the downstream end of the burner cylinder can be further reduced.

  Further, in any one of the above combustors, at the downstream end portion of the burner cylinder, a tapered surface is formed so that the inner diameter gradually increases toward the downstream side, and the cylinder forming the burner cylinder The taper surface forming width of the tapered surface in the plate thickness direction of the forming plate may be half or more of the plate thickness in the portion where the tapered surface is not formed on the tube forming plate.

  In the combustor, most of the combustible gas in the burner cylinder smoothly flows toward the downstream side even immediately after the flammable gas is ejected from the burner cylinder. Therefore, in the combustor, it is possible to reduce the vortices formed on the downstream side of the downstream end of the burner cylinder.

  In any of the above combustors, the substrate may be formed with a plurality of purge air holes penetrating from the purge air space to the downstream side of the substrate.

  In the combustor, thermal damage of the substrate can be suppressed.

  Further, in any one of the combustors described above, in the region where the fuel concentration is relatively high in the circumferential direction around the burner axis on the downstream side of the burner cylinder, the ejection per unit length in the circumferential direction The area of the opening may be large.

  In the combustor, the flow rate of purge air ejected from the ejection opening can be increased in a region where the fuel concentration is relatively high in the circumferential direction centering on the burner axis downstream of the burner cylinder. Therefore, in the combustor, the possibility of the formation of a flame near the downstream end of the burner cylinder can be reduced.

Further, a combustor as another aspect according to the invention for achieving the above object is as follows:
A nozzle having a rod-like portion centered on the burner axis, a nozzle for injecting fuel, and a tubular shape surrounding the outer periphery of the nozzle and extending from the upstream side which is one side in the axial direction from which the burner axis extends The burner cylinder which ejects the air and the fuel from the nozzle, and the downstream end of the burner cylinder in a direction having a radial component based on the burner axis, A plurality of purge airs penetrating from the purge air space to the downstream side of the substrate. A hole is formed, and a tapered surface is formed at the downstream end of the burner cylinder so that the inner diameter gradually increases toward the downstream side, and in the thickness direction of the cylinder forming plate forming the burner cylinder Said te Tapered surface formation width of tapered surface is not less than half the plate thickness in the barrel the tapered surface is forming plate is not formed partially.

  In the combustor, most of the combustible gas in the burner cylinder smoothly flows toward the downstream side even immediately after the flammable gas is ejected from the burner cylinder. Therefore, in the combustor, it is possible to reduce the vortices formed on the downstream side of the downstream end of the burner cylinder. Moreover, in the combustor, the purge air in the purge air space is jetted downstream of the substrate. Therefore, in the combustor, combustion of combustible gas in the vicinity of the downstream end of the burner cylinder can be suppressed.

In addition, a gas turbine as one aspect according to the invention for achieving the above object is as follows:
Any of the above combustors, a compressor that compresses air and supplies air to the combustor, and a turbine that is driven by combustion gas formed by combustion of fuel in the combustor, Have.

  In one aspect according to the present invention, thermal damage and the like of the burner cylinder can be suppressed, and the life of the combustor can be extended.

It is a mimetic diagram showing the composition of the gas turbine in one embodiment concerning the present invention. It is a sectional view around a burner of a gas turbine in one embodiment concerning the present invention. It is sectional drawing of the fuel device in one Embodiment which concerns on this invention. It is a sectional view of a burner around a burner in one embodiment concerning the present invention. It is a V arrow line view in FIG. It is sectional drawing of the combustor around the burner in a comparative example. It is a sectional view of a burner of the circumference of a burner in the first modification concerning the present invention. It is a sectional view of a burner around a burner in the 2nd modification concerning the present invention. It is sectional drawing of the combustor around a burner in the 3rd modification concerning this invention. It is sectional drawing of the combustor around a burner in the 4th modification concerning this invention. It is sectional drawing of the combustor around a burner in the 5th modification concerning the present invention. It is a front view of the burner in the 6th modification concerning the present invention. It is the XIII-XIII sectional view taken on the line in FIG. It is a front view of the combustor around a burner in the 7th modification concerning the present invention. It is sectional drawing of the combustor around a burner in the 8th modification concerning this invention.

  Hereinafter, an embodiment of a gas turbine according to the present invention and various modifications of a combustor included in the gas turbine will be described in detail with reference to the drawings.

"Embodiment"
An embodiment of a gas turbine according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the gas turbine of the present embodiment includes a compressor 1 that compresses outside air to generate compressed air, and a plurality of combustors 4 that generate combustion gas by burning fuel F in the compressed air. And a turbine 5 driven by combustion gas.

  The compressor 1 includes a compressor rotor 2 that rotates about a rotation axis Ar, and a compressor casing 3 that covers the compressor rotor 2 rotatably. The turbine 5 includes a turbine rotor 6 that rotates about a rotation axis Ar, and a turbine casing 7 that rotatably covers the turbine rotor 6. The rotation axis Ar of the compressor rotor 2 and the rotation axis Ar of the turbine rotor 6 are located on the same straight line. The compressor rotor 2 and the turbine rotor 6 are connected to each other to form a gas turbine rotor 8. The compressor casing 3 and the turbine casing 7 are connected to each other to form a gas turbine casing 9.

  For example, a generator rotor is connected to the gas turbine rotor 8. Further, a combustor 4 is fixed to the gas turbine casing 9.

  As shown in FIG. 2, the combustor 4 is a combustion cylinder (or tail cylinder) that burns fuel F inside and sends combustion gas generated as a result of combustion of the fuel F to the combustion gas flow path of the turbine 5. 10 and a fuel ejector 20 that ejects fuel F and air A into the combustion cylinder 10.

  As shown in FIG. 3, the combustion cylinder 10 has a cylindrical shape centered on the combustor axis Ac, and a combustion portion 11 that forms a combustion region 19 in which fuel ejected from the fuel injector 20 burns, and a cylindrical shape. And a combustion gas guiding portion 15 for guiding the combustion gas generated by the combustion of the fuel to the combustion gas flow path of the turbine 5. Here, a direction in which the combustor axis Ac extends is referred to as an axial direction Da, one side of the axial direction Da is referred to as an upstream side, and the other side is referred to as a downstream side. The combustion gas guide portion 15 of the combustion cylinder 10 is formed on the downstream side of the combustion section 11 of the combustion cylinder 10.

  The fuel ejector 20 includes a plurality of burners 30 that eject air together with fuel, and a burner holding cylinder 21 that holds the plurality of burners 30.

  The burner 30 swirls compressed air around the burner axis Ab, a rod-shaped nozzle 31 extending in the axial direction Da around the burner axis Ab parallel to the combustor axis Ac, a burner cylinder 33 covering the outer periphery of the nozzle 31 And a plurality of swivel plates 32.

  The nozzle 31 is formed with an injection hole for injecting fuel. The nozzle 31 is provided with a plurality of revolving plates 32. Each swivel plate 32 extends from the outer periphery of the nozzle 31 in a direction including a radial component, and is connected to the inner peripheral surface of the burner cylinder 33. Compressed air compressed by the compressor 1 flows into the burner cylinder 33 from the upstream side. The burner cylinder 33 ejects the fuel injected from the nozzle 31 together with the compressed air from its downstream end.

  Note that all of the plurality of burners 30 may be premixed combustion burners in which fuel and air are premixed in the burner cylinder 33 and ejected as a premixed gas. It may be a diffusion combustion burner that ejects these without premixing the air and air. Moreover, some burners among the plurality of burners 30 may be premixed combustion burners, and the remaining burners may be diffusion combustion burners.

  When the burner 30 is a premixed combustion burner, an injection hole for injecting fuel may be formed in the swirl plate 32, and fuel may be injected into the burner cylinder 33 from here. In this case, a portion corresponding to the rod-shaped nozzle 31 described above forms a hub rod, and the nozzle is formed by having the hub rod and a plurality of swiveling plates 32. Fuel from the outside is supplied into the hub rod, and fuel is supplied to the pivot plate 32 from the hub rod. As described above, the burner 30 ejects a combustible gas containing fuel and air, regardless of whether it is a premixed combustion burner or a diffusion combustion burner.

  The fuel sprayer 20 further includes a substrate 22 extending from the downstream end of each burner cylinder 33 in the radial direction with respect to each burner axis Ab. The substrate 22 has a disk shape around the combustor axis Ac and the outer peripheral edge thereof is connected to the burner holding cylinder 21. This substrate 22 defines a purge air space 29 into which purge air Pa flows on the outer peripheral side of each burner cylinder 33 and on its upstream side, and also defines the above-described combustion region 19 on its downstream side.

  As shown in FIGS. 4 and 5, a plurality of purge air holes 25 penetrating from the purge air space 29 to the combustion region 19 are formed in the substrate 22. Further, the substrate 22 and each burner cylinder 33 are formed with a purge air slit (purge air flow path) 40 penetrating from the purge air space 29 to the combustion region 19 so as to straddle them. An inlet opening 41, which is an opening on the purge air space 29 side of the purge air slit 40, is formed on the upstream side surface 23 of the substrate 22. The ejection opening 42 of the purge air slit 40 is formed at a corner of the downstream end of the burner cylinder 33.

  The purge air slit 40 is cylindrical with the burner axis Ab as the center. Therefore, both the inlet opening 41 and the jet opening 42 of the purge air slit 40 are annular around the burner axis Ab. Further, the purge air slit 40 is linearly inclined such that the flow path in the virtual plane including the burner axis Ab gradually approaches the burner axis Ab as it goes from the inlet opening 41 toward the ejection opening 42.

  As described above, the ejection opening 42 is formed at the corner of the downstream end of the burner cylinder 33, that is, at the corner of the inner peripheral surface of the burner cylinder 33 and the downstream end surface 34 of the burner cylinder 33. Therefore, the ejection opening 42 has a range from the downstream end surface 34 of the burner cylinder 33 toward the first opening formation range dimension tb toward the upstream side, and the first opening in the radial direction from the inner circumferential surface of the burner cylinder 33 It is formed within a first opening formation range consisting of a range up to the formation range dimension tb. The first opening formation range dimension is the longer one of the plate thickness dimension ta of the tube forming plate 35 forming the burner tube 33 and the plate thickness dimension tb of the substrate 22. Here, the plate thickness dimension ta of the tube forming plate 35 is shorter than the plate thickness dimension tb of the substrate 22. Therefore, the first opening formation range dimension here is the plate thickness dimension tb of the substrate 22. Furthermore, the ejection opening 42 has a range from the downstream end surface 34 of the burner cylinder 33 toward the upstream side to the second opening formation range dimension ta and a second opening in the radial direction from the inner circumferential surface of the burner cylinder 33 It is formed within a second opening forming range comprising a range up to the forming range dimension ta. The second opening forming range dimension is a shorter one of the plate thickness dimension ta of the tube forming plate 35 forming the burner tube 33 and the plate thickness dimension tb of the substrate 22. Therefore, the second opening formation range dimension here is the plate thickness dimension ta of the tube forming plate 35.

  Here, the flow of gas in a comparative example in which the purge air slit is not formed in any of the burner cylinder 33 and the substrate 22 will be described with reference to FIG.

  From the burner cylinder 33x of the comparative example, the combustible gas IG is ejected into the combustion region 19 of the combustion cylinder 10 (see FIG. 3).

  When the purge air slit is not formed in the burner cylinder 33x and the substrate 22x, a vortex flow of the combustible gas IG flowing in the burner cylinder 33x is formed on the downstream side of the downstream end face 34 of the burner cylinder 33x.

  As described above, when a vortex of the combustible gas IG is formed on the downstream side of the downstream end face 34 of the burner cylinder 33x, it is formed in the vicinity of the downstream end face 34 of the burner cylinder 33x and the downstream side face 24 near the burner cylinder 33x of the substrate 22x. Depending on the operation state of the combustor, a flame may be formed in the vicinity of the downstream end surface 34 of the burner cylinder 33x and in the vicinity of the downstream side surface 24 near the burner cylinder 33x of the substrate 22x. For this reason, the downstream end portion of the burner cylinder 33x and the portion of the substrate 22x close to the burner cylinder 33x are placed in a high-temperature environment, and the burner cylinder 33x and the substrate 22x are damaged by heat and the life thereof is shortened.

  On the other hand, in this embodiment, the purge air slit 40 extending from the substrate 22 to the burner cylinder 33 is formed, and the ejection opening 42 is formed at the corner of the downstream end of the burner cylinder 33. In addition, the purge air slit 40 is inclined so that the flow passage in the virtual plane including the burner axis Ab gradually approaches the burner axis Ab as it goes from the inlet opening 41 to the ejection opening 42. Therefore, the purge air Pa from the purge air space 29 is ejected from the corner of the downstream end portion of the burner cylinder 33 into the combustion region 19 in a direction gradually approaching the burner axis Ab as it goes downstream. Therefore, in this embodiment, not only the vortex of the combustible gas IG is substantially not formed on the downstream side of the downstream end face 34 of the burner cylinder 33, but also the radiation of the combustible gas IG ejected from the burner cylinder 33 to the burner axis Ab. The spread of the direction can be suppressed. Even if a part of the combustible gas IG ejected from the burner cylinder 33 drifts in the vicinity of the downstream end face 34 of the burner cylinder 33, the combustible component in the combustible gas IG is diluted by the purge air Pa. In other words, the purge air Pa from the purge air slit 40 drifts in the vicinity of the downstream end of the burner cylinder 33, and the combustible component in the combustible gas IG drifts in the vicinity of the downstream end of the burner cylinder 33 decreases.

  Therefore, in the present embodiment, the combustion of the combustible gas IG near the downstream end of the burner cylinder 33 can be suppressed. For this reason, in this embodiment, the thermal damage etc. of the burner cylinder 33 and the board | substrate 22 can be suppressed, and these lifetimes can be lengthened.

“First variation of combustor”
A first modification of the combustor in the above embodiment will be described with reference to FIG.

  The combustor of this modification is obtained by changing the shape of the purge air slit 40 in the combustor of the above-described embodiment, and is otherwise the same as the combustor of the above-described embodiment.

  The inlet opening 41 a of the purge air slit 40 a in the present modification is formed on the upstream side surface 23 of the substrate 22. Further, the ejection opening 42 a of the purge air slit 40 a is formed on the downstream end surface 34 of the burner cylinder 33. Therefore, this ejection opening 42a is formed in the second opening formation range from the inner peripheral surface of the burner cylinder 33 to the position corresponding to the plate thickness dimension ta of the cylinder forming plate 35 in the radial direction, as in the above embodiment. .

  The purge air slit 40a has a first flow path 45a extending from the inlet opening 41a toward the downstream side in the substrate 22 and a burner in the cylinder forming plate 35 that forms the substrate 22 and the burner cylinder 33 from the downstream end of the first flow path 45a. A third flow having a second flow passage 46a extending inward in the radial direction with respect to the axis Ab and a flow extending toward the downstream side in the cylinder forming plate 35 from the radial inner end of the second flow passage 46a And a passage 47a. That is, in the purge air slit 40a, the flow passage in the virtual plane including the burner axis Ab has a crank shape.

  In this modification, a purge air slit 40 a extending from the substrate 22 to the burner cylinder 33 is formed, and the ejection opening 42 a is formed in the downstream end face 34 of the burner cylinder 33. A third flow path 47a having the ejection opening 42a as an opening extends toward the downstream side. For this reason, purge air Pa from the purge air space 29 is jetted from the downstream end face 34 of the burner cylinder 33 into the combustion area 19 toward the downstream side. Therefore, also in this modification, not only the vortex of the combustible gas IG is not substantially formed on the downstream side of the downstream end face 34 of the burner cylinder 33 as in the above embodiment, but also the combustible gas IG ejected from the burner cylinder 33. The spread of the radial direction with respect to the burner axis Ab can be suppressed. Even if a part of the combustible gas IG ejected from the burner cylinder 33 drifts in the vicinity of the downstream end face 34 of the burner cylinder 33, the combustible component in the combustible gas IG is diluted by the purge air Pa.

  Therefore, in the present modification as well, thermal damage and the like of the burner cylinder 33 and the substrate 22 can be suppressed, and their lifetime can be extended.

"Second variation of combustor"
A second modification of the combustor in the embodiment will be described with reference to FIG.

  The combustor of this modification is also a modification of the shape of the purge air slit 40 in the combustor of the above embodiment, and the other configurations are the same as those of the combustor of the above embodiment.

  The inlet opening 41 b of the purge air slit 40 b in the present modification is formed on the outer peripheral surface of the burner cylinder 33. Further, the ejection opening 42 b of the purge air slit 40 b is formed on the inner peripheral surface of the burner cylinder 33. The ejection opening 42b is formed on the inner peripheral surface of the burner cylinder 33 and within the second opening formation range from the downstream end surface 34 of the burner cylinder 33 to the upstream side at a position corresponding to the plate thickness dimension ta of the cylinder formation plate 35. It is done.

  The purge air slit 40b includes a first flow path 45b extending from the inlet opening 41b toward the downstream side in the cylinder forming plate 35, and a radial inner side in the cylinder forming plate 35 from the downstream end of the first flow path 45b to the burner axis Ab. The second flow path 46b is formed to extend toward the ejection opening 42b. That is, in the purge air slit 40b, as in the first modification, the flow path in the imaginary plane including the burner axis Ab forms a crank shape.

  In this modification, the purge air slit 40b is formed in the burner cylinder 33, and the ejection opening 42b is formed on the inner peripheral surface of the burner cylinder 33 within the second opening formation range. In addition, a second flow passage 46b having the ejection opening 42b as an opening extends radially inward with respect to the burner axis Ab. For this reason, the purge air Pa from the purge air space 29 is jetted into the burner cylinder 33 from the inner peripheral surface of the burner cylinder 33 toward the radially inner side from the second opening formation range. The flow of the purge air Pa is changed to the flow toward the downstream side by the combustible gas IG flowing to the downstream side in the burner cylinder 33. On the other hand, the flammable gas IG is pushed toward the side closer to the burner axis Ab by the purge air Pa which is an inner peripheral surface of the burner cylinder 33 and jets radially inward from the second opening formation range. Therefore, also in this modification, not only the vortex of the combustible gas IG is not substantially formed on the downstream side of the downstream end face 34 of the burner cylinder 33 as in the above embodiment, but also the combustible gas IG ejected from the burner cylinder 33. The spread of the radial direction with respect to the burner axis Ab can be suppressed. Even if a part of the combustible gas IG ejected from the burner cylinder 33 drifts in the vicinity of the downstream end face 34 of the burner cylinder 33, the combustible component in the combustible gas IG is diluted by the purge air Pa.

  Therefore, in the present modification as well, thermal damage and the like of the burner cylinder 33 and the substrate 22 can be suppressed, and their lifetime can be extended.

"Third modification of combustor"
A third modification of the combustor in the embodiment will be described with reference to FIG.

  The combustor of this modification is also a modification of the shape of the purge air slit 40 in the combustor of the above embodiment, and the other configurations are the same as those of the combustor of the above embodiment.

  The inlet opening 41 c of the purge air slit 40 c in the present modification is formed on the outer peripheral surface of the burner cylinder 33. Further, the ejection opening 42 c of the purge air slit 40 c is formed on the downstream end surface 34 of the burner cylinder 33. Therefore, this ejection opening 42c is formed in the second opening formation range from the inner peripheral surface of the burner cylinder 33 to the position corresponding to the plate thickness dimension ta of the cylinder forming plate 35 in the radial direction, as in the above embodiment. .

  The purge air slit 40c extends linearly from the inlet opening 41c toward the downstream side in the cylinder forming plate 35, and is formed only by a flow path having the ejection opening 42c as an opening.

  In this modification, the purge air slit 40 c is formed in the burner cylinder 33, and the ejection opening 42 c is formed in the downstream end face 34 of the burner cylinder 33. Further, in the purge air slit 40c, a flow passage having the ejection opening 42c as an opening extends toward the downstream side. For this reason, purge air Pa from the purge air space 29 is jetted from the downstream end face 34 of the burner cylinder 33 into the combustion area 19 toward the downstream side. Therefore, in this modified example, as in the above-described embodiment and the first modified example, not only a vortex of the combustible gas IG is substantially not formed on the downstream side of the downstream end surface 34 of the burner tube 33, but the burner tube 33 is ejected. It is possible to suppress the spread of the flammable gas IG in the radial direction with respect to the burner axis Ab. Even if a part of the combustible gas IG ejected from the burner cylinder 33 drifts in the vicinity of the downstream end face 34 of the burner cylinder 33, the combustible component in the combustible gas IG is diluted by the purge air Pa.

  Therefore, in the present modification as well, thermal damage and the like of the burner cylinder 33 and the substrate 22 can be suppressed, and their lifetime can be extended.

  Further, in this modification, since the purge air slit 40c is formed only by the flow passage extending linearly in the cylinder forming plate 35, the purge air slit 40c is formed more than the purge air slits 40a and 40b in the first and second modifications. Is easy.

"Fourth variation of combustor"
A fourth modification of the combustor in the embodiment will be described with reference to FIG.

  The combustor of this modification is obtained by changing the arrangement of the purge air slit 40 in the combustor of the above embodiment, and the other configurations are the same as those of the combustor of the above embodiment.

  The inlet opening 41 d of the purge air slit 40 d in the present modification is formed on the upstream side surface 23 of the substrate 22. Further, the ejection opening 42 d of the purge air slit 40 d is formed on the downstream side surface 24 of the substrate 22. The ejection opening 42d is formed on the downstream side surface 24 of the substrate 22 and within the first opening formation range from the inner peripheral surface of the burner cylinder 33 to the position corresponding to the plate thickness dimension tb of the substrate 22 in the radial direction. . The purge air slit 40d is inclined and linear so that the flow path in the imaginary plane including the burner axis Ab gradually approaches the burner axis Ab as it goes from the inlet opening 41d toward the ejection opening 42d.

  In this modification, the purge air slit 40d is formed in the substrate 22, and the ejection opening 42d is formed on the downstream side surface 24 of the substrate 22 within the first opening formation range. Further, the flow path in the virtual plane including the burner axis Ab in the purge air slit 40d is inclined so as to gradually approach the burner axis Ab from the inlet opening 41d toward the ejection opening 42d. For this reason, the purge air Pa from the purge air space 29 is ejected from the downstream side surface 24 of the substrate 22 within the first opening formation range toward the burner axis Ab gradually toward the downstream side. Therefore, in this modification, not only the vortex of the combustible gas IG is substantially not formed on the downstream side of the downstream end face 34 of the burner cylinder 33, but also the radiation of the combustible gas IG ejected from the burner cylinder 33 to the burner axis Ab. The spread of the direction can be suppressed. Even if a part of the combustible gas IG ejected from the burner cylinder 33 drifts in the vicinity of the downstream end face 34 of the burner cylinder 33, the combustible component in the combustible gas IG is diluted by the purge air Pa. In other words, the purge air Pa from the purge air slit 44d drifts in the vicinity of the downstream end of the burner cylinder 33, and the combustible component in the combustible gas IG drifts in the vicinity of the downstream end of the burner cylinder 33 decreases. Therefore, also in the present modification, the combustion of the flammable gas IG near the downstream end of the burner cylinder 33 can be suppressed.

  As described above, even if the ejection opening 42d of the purge air slit 40d is not formed within the second opening formation range, the burner cylinder 33 may be formed within the first opening formation range wider than this range. In the vicinity of the downstream end of the combustion of the combustible gas IG can be suppressed. For this reason, in this modification, the thermal damage etc. of the burner cylinder 33 and the board | substrate 22 can be suppressed, and these lifetimes can be lengthened. Therefore, also in the first modified example, the second modified example, the third modified example, and the fifth modified example described later, the ejection opening of the purge air slit may be formed within the first opening forming range.

"Fifth modification of combustor"
A fifth modification of the combustor in the embodiment will be described with reference to FIG.

  In the combustor according to the above-described embodiment and each of the modifications described above, the downstream end surface 34 of the burner cylinder 33 and the downstream side surface 24 of the substrate 22 are flush with each other. On the other hand, in the combustor of this modification, the downstream end surface 34 of the burner cylinder 33 protrudes further downstream than the downstream side surface 24 of the substrate 22.

  The inlet opening 41 e of the purge air slit 40 e in the present modification is formed on the upstream side surface 23 of the substrate 22. Further, the ejection opening 42 e of the purge air slit 40 e is formed on the inner peripheral surface of the burner cylinder 33. The ejection opening 42e is an inner circumferential surface of the burner cylinder 33, and is formed in the second opening formation range from the downstream end surface 34 of the burner cylinder 33 to the upstream side at a position corresponding to the plate thickness dimension ta of the cylinder forming plate 35. It is done. The purge air slit 40e is linearly inclined so as to gradually approach the burner axis Ab as the flow path in the virtual plane including the burner axis Ab moves from the inlet opening 41e toward the ejection opening 42e.

  In this modification, a purge air slit 40e is formed extending from the substrate 22 to the burner cylinder 33, and the jet opening 42e is formed on the inner peripheral surface of the burner cylinder 33 and within the second opening formation range. Further, the flow path in the virtual plane including the burner axis Ab in the purge air slit 40e is inclined so as to gradually approach the burner axis Ab as it goes from the inlet opening 41e to the ejection opening 42e. For this reason, the purge air Pa from the purge air space 29 is ejected from the inner peripheral surface of the burner cylinder 33 within the second opening formation range toward the burner axis Ab gradually toward the downstream side. . Therefore, in this modification, not only the vortex of the combustible gas IG is substantially not formed on the downstream side of the downstream end face 34 of the burner cylinder 33, but also the radiation of the combustible gas IG ejected from the burner cylinder 33 to the burner axis Ab. The spread of the direction can be suppressed. Even if a part of the combustible gas IG ejected from the burner cylinder 33 drifts in the vicinity of the downstream end face 34 of the burner cylinder 33, the combustible component in the combustible gas IG is diluted by the purge air Pa.

  As described above, even if the downstream end surface 34 of the burner cylinder 33 and the downstream side surface 24 of the substrate 22 are not flush with each other, the purge air slit is formed in the second opening formation range or in the first opening formation range wider than this. If the ejection opening is formed, thermal damage or the like of the burner cylinder 33 or the substrate 22 can be suppressed, and the life of these can be extended. Therefore, also in the embodiment and the first to fourth modifications described above, the downstream end surface 34 of the burner cylinder 33 and the downstream side surface 24 of the substrate 22 do not have to be flush with each other.

"Sixth variation of combustor"
A sixth modification of the combustor in the embodiment will be described with reference to FIGS. 12 and 13.

  The inlet opening 41 and the ejection opening 42 of the purge air slit 40 in the above embodiment are both annular around the burner axis Ab. On the other hand, the inlet opening 41f and the jet opening 42f of the purge air slit 40f in the present modification are both formed in a plurality separated from each other in the circumferential direction Dc centered on the burner axis Ab. The plurality of inlet openings 41f and the plurality of ejection openings 42f are all formed in an arc shape with the burner axis Ab as the center. Therefore, a plurality of purge air slits 40f in this modification are formed apart from each other in the circumferential direction Dc around the burner axis Ab. Between the plurality of purge air slits 40f in the circumferential direction Dc, an interval between the inner peripheral edge and the outer peripheral edge of the arc-shaped inlet opening 41f and an interval between the inner peripheral edge and the outer peripheral edge of the arc-shaped ejection opening 42f are ensured. To form a spacer 48f.

  The inlet opening 41f of the purge air slit 40f in the present modification is formed on the upstream side surface 23 (see FIG. 4) of the substrate 22 as in the above embodiment. Further, the ejection opening 42f of the purge air slit 40f is formed at the corner of the downstream end of the burner cylinder 33, as in the above embodiment. Further, the purge air slit 40f is linearly inclined so as to gradually approach the burner axis Ab as the flow path in the virtual plane including the burner axis Ab moves from the inlet opening 41f toward the ejection opening 42f. Therefore, the combustor of this modification is the combustor of the above embodiment with the addition of the spacer 48f, and the other configuration is the same as the combustor of the above embodiment.

  Therefore, also in this modified example, the thermal damage of the burner cylinder 33 and the board | substrate 22 etc. can be suppressed fundamentally similarly to the said embodiment, and these lifetimes can be lengthened.

  Further, in this modification, since the spacer 48f is provided, the distance between the inner peripheral edge and the outer peripheral edge of the arc-shaped inlet opening 41f and the distance between the inner peripheral edge and the outer peripheral edge of the arc-shaped ejection opening 42f are easily made. It can be secured.

  However, in this modification, since the spacer 48f is provided, a small vortex is formed on the downstream side of the spacer 48f. The downstream side of the spacer 48 f is the downstream side of the flow of the purge air Pa in the purge air slit 40 f. Therefore, the spacer 48f is formed such that the width dimension in the circumferential direction Dc is reduced or the width dimension in the circumferential direction Dc is gradually reduced toward the downstream side (the ejection opening 42f side) as shown in FIG. It is preferable to make the vortices formed on the downstream side of the spacer 48 f smaller.

  In the present modification, a plurality of inlet openings 41f and ejection openings 42f are formed apart from each other in the circumferential direction Dc centered on the burner axis Ab. However, among the inlet openings 41f and the jet openings 42f, only one of the openings may be separated from each other in the circumferential direction Dc, and the other openings may be annularly formed around the burner axis Ab.

  Moreover, although this modification adds the spacer 48f to the combustor of the said embodiment, you may add the same spacer to the combustor of the above-mentioned 1st modification-5th modification.

  In this modification, the spacers 48f are arranged at equal intervals in the circumferential direction Dc. However, in the region where the fuel concentration distribution in the circumferential direction Dc of the combustible gas IG is relatively high, the area of the ejection opening per unit length in the circumferential direction Dc may be made larger than in other regions. As a method of increasing the area of the jet opening per unit length in the circumferential direction Dc, there is, for example, a method of widening the interval between the adjacent spacers 48f or a method of reducing the thickness of the spacer 48f in the circumferential direction Dc. . As a result, the purge air flow rate in the region where the fuel concentration distribution is relatively high increases, and the possibility that a flame is formed near the downstream end of the burner cylinder 33 can be reduced.

  For the same purpose, in the region where the fuel concentration distribution in the circumferential direction Dc of the combustible gas IG is relatively high even if the spacer is not provided and the ejection opening has an annular shape, the unit in the circumferential direction Dc The area of the jet opening per length may be larger than that of the other area. As a method of increasing the area of the ejection opening per unit length in the circumferential direction Dc, for example, there is a method of increasing the width of the ejection opening in the radial direction.

"Seventh Variation of Combustor"
A seventh modification of the combustor in the above embodiment will be described with reference to FIG.

  Although annular or slit-like flow paths separated from each other are provided as the purge air flow path in the embodiment and the modification, the invention is not limited thereto. For example, as shown in FIG. 14, a plurality of purge air through holes 40g spaced apart from each other may be provided in the circumferential direction Dc with the burner axis Ab as the center, as the purge air flow path.

  The ejection opening 42g of the purge air through hole 40g in this modification is formed at the corner of the downstream end portion of the burner cylinder 33. About another structure, it is the same as the combustor of the said embodiment.

  Therefore, also in this modified example, the thermal damage of the burner cylinder 33 and the board | substrate 22 etc. can be suppressed fundamentally similarly to the said embodiment, and these lifetimes can be lengthened.

  Moreover, this modification is provided with a plurality of purge air through holes 40g as purge air channels instead of the purge air slits 40 as the purge air channels in the embodiment shown in FIGS. 4 and 5. is there. However, a plurality of purge air through holes may be provided in place of the purge air slits of the combustors of the first to sixth modifications.

  Furthermore, in this modification, as shown in FIG. 14, the purge air through holes 40g and the ejection openings 42g are arranged at equal intervals in the circumferential direction Dc with the same diameter. However, in the region where the fuel concentration distribution in the circumferential direction of the combustible gas IG is relatively high, the area of the ejection opening per unit length in the circumferential direction Dc may be larger than in other regions. As a method of increasing the area of the ejection openings per unit length in the circumferential direction Dc, for example, there are a method of increasing the diameters of the purge air through holes 40g and the ejection openings 42g, and a method of increasing the number thereof. As a result, the purge air flow rate in the region where the fuel concentration distribution is relatively high increases, and the possibility that a flame is formed near the downstream end of the burner cylinder 33 can be reduced.

"Eighth modification of combustor"
An eighth modification of the combustor in the above embodiment will be described with reference to FIG.

  The combustor according to the present modification has an inner diameter that gradually increases toward the downstream side at the downstream end of the burner cylinder 33 instead of the purge air slit being formed in either the burner cylinder 33 or the substrate 22. A tapered surface 36 is formed so as to be. The tapered surface forming width tw of the tapered surface 36 in the thickness direction of the cylinder forming plate 35 forming the burner cylinder 33 is half or more of the plate thickness ta in the portion where the tapered surface 36 is not formed in the cylinder forming plate 35.

  By forming the tapered surface 36 at the downstream end portion of the burner cylinder 33 as in the present modification, almost immediately after the combustible gas IG in the burner cylinder 33 is ejected from the burner cylinder 33, most of it is directed toward the downstream side. It flows smoothly. For this reason, it is difficult to form a vortex of the combustible gas IG on the downstream side of the downstream end of the burner cylinder 33, and the possibility that a flame is formed in the vicinity of the downstream end of the burner cylinder 33 can be reduced. For this reason, also in this modification, the thermal damage etc. of the burner cylinder 33 and the board | substrate 22 are suppressed, and these lifetimes can be lengthened.

  By the way, the effect of suppressing the generation of eddy currents can be expected to some extent if the tapered surface 36 is formed even at the downstream end of the burner cylinder 33. However, if the taper surface formation width tw in the plate thickness direction of the taper surface 36 is less than half of the plate thickness ta in the portion where the taper surface 36 is not formed on the tube forming plate 35, the downstream of the downstream end of the burner tube 33. On the side, a swirl of the flammable gas IG is likely to be formed. Moreover, the vortex increases the possibility that a flame is formed near the downstream end of the burner cylinder 33.

  On the other hand, when the tapered surface forming width tw in the plate thickness direction of the tapered surface 36 is half or more of the plate thickness ta in the portion where the tapered surface 36 is not formed by the cylinder forming plate 35, the downstream of the burner cylinder 33 Even if a vortex of the combustible gas IG is formed on the downstream side of the end, the size thereof is reduced. Thus, with a small vortex, the possibility of the formation of a flame near the downstream end of the burner cylinder 33 is extremely reduced. For this reason, in this modification, the tapered surface forming width tw in the plate thickness direction of the tapered surface 36 is set to half or more of the plate thickness ta in the portion where the tapered surface 36 is not formed by the cylinder forming plate 35.

  The tapered surface 36 in the present modification includes the burner axis Ab and the shape on the virtual plane that crosses the tapered surface 36 is a straight line, but the inner diameter of the burner cylinder 33 gradually increases toward the downstream side. If it is a plane, the shape on the imaginary plane including the burner axis Ab and crossing the plane may be a curve.

  In addition, the present modification is an example in which the purge air flow path is not formed in either the burner cylinder 33 or the substrate 22, but also in the present modification, the embodiment and the first to seventh modifications are described. As an example, a purge air flow path may be formed in at least one of the burner cylinder 33 and the substrate 22.

  1: compressor, 4: combustor, 5: turbine, 10: combustion cylinder, 11: combustion section, 15: combustion gas guide section, 19: combustion region, 20: fuel injector, 22: substrate, 23: upstream side surface , 24: downstream side, 25: purge air hole, 29: purge air space, 30: burner, 31: nozzle, 32: swirl plate, 33: burner cylinder, 34: downstream end surface, 35: cylinder forming plate, 36: taper 40, 40a, 40b, 40c, 40d, 40e, 40f: purge air slit (purge air flow path), 40g: purge air through hole (purge air flow path), 41, 41a, 41b, 41c, 41d, 41e , 41f: inlet opening, 42, 42a, 42b, 42c, 42d, 42e, 42f, 42g: ejection opening, 48f: spacer, Ab: burner axis, Ac: combustor axis, Da: axial direction, Dc: circumferential direction IG: flammable gas, Pa: purge air

Claims (14)

A nozzle having a rod-like portion centered on the burner axis and injecting fuel;
A burner cylinder which forms a cylindrical shape and surrounds the outer periphery of the nozzle, and which jets air and fuel from the nozzle from the upstream side, which is one side in the axial direction along which the burner axis extends, to the downstream side, which is the other side ,
From the downstream end of the burner cylinder, it spreads in a direction having a radial component based on the burner axis, and defines a purge air space into which purge air flows in the outer peripheral side of the burner cylinder and upstream of itself. A substrate to be
Equipped with
A purge air flow path for ejecting the purge air in the purge air space into the burner cylinder or downstream of the substrate is formed in at least one of the substrate and the burner cylinder;
The thickness of the cylinder forming plate that forms the burner cylinder and the thickness of the substrate are from the downstream end of the burner cylinder to the upstream side of the ejection opening that ejects the purge air in the purge air flow channel. Among these, from the range up to the first opening formation range dimension, which is the longer plate thickness dimension, and the range from the inner peripheral surface of the burner tube to the first opening formation range dimension in the radial direction Formed in the first opening forming area,
Burner. A nozzle having a rod-like portion centered on the burner axis and injecting fuel;
A burner cylinder which forms a cylinder and surrounds the outer periphery of the nozzle, and jets air and fuel from the nozzle from the upstream side which is one side in the axial direction in which the burner axis extends to the downstream side which is the other side; ,
From the downstream end of the burner cylinder, it spreads in a direction having a radial component based on the burner axis, and defines a purge air space into which purge air flows in the outer peripheral side of the burner cylinder and upstream of itself. A substrate to be
Equipped with
A purge air flow path for ejecting the purge air in the purge air space into the burner cylinder or downstream of the substrate is formed in at least one of the substrate and the burner cylinder;
The ejection opening for ejecting the purge air in the purge air flow path has a plate thickness dimension of a cylinder forming plate that forms the burner cylinder and a plate thickness dimension of the substrate from the downstream end of the burner cylinder toward the upstream side. And the range up to the second opening formation range dimension which is the shorter plate thickness dimension, and the range from the inner peripheral surface of the burner tube to the second opening formation range dimension in the radial direction. Formed in the second opening formation range,
Burner. The combustor according to claim 1 or 2,
The ejection opening is formed in an annular shape around the burner axis.
Burner. The combustor according to claim 1 or 2,
A plurality of the ejection openings are formed apart from each other in the circumferential direction around the burner axis.
Burner. The combustor according to any one of claims 1 to 3.
At least one of the inlet opening through which the purge air flows in the purge air flow path and the ejection opening is formed in a plurality separated from each other in the circumferential direction around the burner axis, One opening is formed in the circular arc shape centering on the said burner axis line, The combustor. The combustor according to claim 5.
Between the plurality of one openings in the circumferential direction, a spacer is provided to secure a distance between the inner peripheral edge and the outer peripheral edge of the one circular opening.
The spacer gradually decreases in circumferential width as it approaches the jet opening from the purge air space side.
Burner. The combustor according to any one of claims 1 to 6,
The ejection opening is formed so as to straddle the substrate and the burner cylinder.
Burner. The combustor according to any one of claims 1 to 6.
The jet opening is formed in the burner cylinder,
Burner. The combustor according to any one of claims 1 to 6.
The jet opening is formed in the substrate,
Burner. The combustor according to any one of claims 1 to 9.
The purge air flow path is inclined to gradually approach the burner axis as it approaches the jet opening from the purge air space side.
Burner. The combustor according to any one of claims 1 to 10.
A tapered surface is formed at the downstream end of the burner cylinder so that the inner diameter gradually increases toward the downstream side, and the taper of the tapered surface in the thickness direction of the cylinder forming plate forming the burner cylinder The surface forming width is not less than half of the plate thickness in the portion where the tapered surface is not formed in the tube forming plate,
Burner. The combustor according to any one of claims 1 to 11.
The substrate is formed with a plurality of purge air holes penetrating from the purge air space to the downstream side of the substrate.
Burner. The combustor according to any one of claims 1 to 12.
In the region where the fuel concentration is relatively high in the circumferential direction around the burner axis on the downstream side of the burner cylinder, the area of the ejection opening per unit length in the circumferential direction is large.
Burner. The combustor according to any one of claims 1 to 13,
A compressor for compressing the air and supplying the air to the combustor;
A turbine driven by combustion gas formed by combustion of fuel in the combustor;
Equipped with a gas turbine.

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